class Student:
    name = None
    age = None

    def say_hi(self):
        print(f"hi大家好，我是{self.name}")

    def say_hello(self, msg):
        print(f"hello大家好，我是{self.name}，{msg}")


stu = Student()
stu.name = "小美"

stu.say_hi()
stu.say_hello("很高兴认识大家")
